Phil Mickelson will not be competing in this year's Masters tournament, according to the organisers' official website.

The 51-year-old had been among the list of participants until Monday, but he has now been moved to a section listed as "past champions not playing".

A three-time Masters winner, this would have been Mickelson's 30th appearance at the major event. 

Mickelson has been the subject of criticism since he claimed a proposed Saudi Arabia-backed Super Golf League could give players "leverage" as a "once-in-a-lifetime opportunity" to "reshape how the PGA Tour operates".

The American suggested he and others had paid lawyers to construct the proposed breakaway competition's agreement, despite acknowledging Saudi Arabia has "a horrible record on human rights".

Mickelson later apologised for what he described as "reckless" comments following huge criticism and is now taking a break from the sport.

The six-time major champion was also a notable absentee from The Players Championship.